DMRT3 Allele Frequencies in Batida- and Picada-Gaited Donkeys and Mules in Brazil.

In Brazil, the production of mules with a comfortable gait primarily involves the breeding of marching saddle mules. This is achieved by crossing gaited Pêga donkeys with horses from the Mangalarga Marchador and Campolina breeds. The DMRT3:g.22999655C>A SNP is implicated in regulating gait phenotypes observed in various horse breeds, including the batida (CC) and picada (CA) gaits found in these horse breeds. We aimed to determine if genotypes influenced gait type in 159 mules and 203 donkeys genotyped for the DMRT3 SNP by PCR-RFLP analysis. About 47% of mules had the CC-genotype, while 53% had the CA-genotype. Donkeys predominantly had the CC-genotype (97%), and none had AA. Both CC- and CA-genotypes were evenly distributed among mules with the batida or picada gaits. In donkeys, the CC-genotype frequencies were consistent regardless of gait type. However, the CA-genotype was more common in picada-gaited donkeys than in batida-gaited donkeys. The prevalence of CA mules and the rare presence of the non-reference allele in donkeys align with previous findings in Mangalarga Marchador and Campolina horses. This suggests that the non-reference allele likely originated from the mares involved in donkey crosses. Our results also imply that factors beyond this variant, such as other genes and polymorphisms, influence gait traits in equids.

Detection of Equus caballus Papillomavirus in Equine Aural Plaque Samples.

Aural plaques have been linked to Equus caballus papillomavirus (EcPV). Ten types of EcPVs have already been described; however, only EcPVs 1, 3, 4, 5, and 6 have been observed in association with aural plaques. Accordingly, the objective of this study was to evaluate the presence of EcPVs in equine aural plaque samples. A total of 29 aural plaque samples (from 15 horses) were collected and assessed for the presence of the DNA of these EcPVs by PCR. Additionally, 108 aural plaque samples used in previous research were evaluated for the presence of EcPVs 8 and 9. Previously described primers were used for PCR to detect EcPVs 1 to 8, and specific primers were designed for EcPV 9. Minigenes were synthesized and used as a positive control in the PCRs for the undetected EcPVs. EcPVs 2, 7, 8, and 9 were not detected in any of the evaluated samples, suggesting that these viral types are not involved in the etiology of the equine aural plaque in Brazil. EcPV 6 was the most prevalent (81%), followed by EcPVs 3 (72%), 4 (63%) and 5 (47%), which reinforces the idea that these viruses play an important role in the etiology of the equine aural plaque in Brazil.

A complex CLCN1 variant associated with hereditary myotonia in a mixed-breed dog.

Hereditary myotonia (HM) is characterized by delayed muscle relaxation after contraction as a result of a mutation in the CLCN1 gene. We describe here a complex CLCN1 variant in a mixed-breed dog with clinical and electromyographic signs of HM. Blood samples from the myotonic dog, as well as from his male littermate and parents, were analyzed via amplification of the 23 exons encoding CLCN1. After sequencing the CLCN1 gene, a complex variant was found in exon 6 c.[705T>G; 708del; 712_732del], resulting in a premature stop codon in exon 7 and a protein that was 717 amino acids shorter than the normal CLC protein. The myotonic dog was identified as homozygous recessive for the complex CLCN1 variant; its parents were heterozygous, and its male littermate was homozygous wild-type. Knowledge of the CLCN1 mutations responsible for the development of hereditary myotonia allows greater clarification of this condition.

Fecal prevalence of Clostridium innocuum DNA in healthy horses and horses with colitis.

This study compared the prevalence of C. innocuum DNA in the feces of healthy horses and horses with acute colitis. C. innocuum was identified in 22% (15/68) of colitis cases and 18% (12/68) of healthy horses (p = 0.416).

Cerebrospinal fluid analysis in horses, cattle, and sheep diagnosed with rabies: A retrospective study of 62 cases.

Objectives: This study aimed to characterize the findings in cerebral spinal fluid (CSF) analysis of horses, cattle, and sheep diagnosed with rabies. Animals: The study included 62 animals (horses, cattle, and sheep) diagnosed with rabies at a referral hospital. Methods: This was a retrospective study using medical records from large animals with neurological signs and confirmed positive direct immunofluorescence test for rabies from 2003 to 2020. The results of CSF analysis are presented descriptively. Results: Cerebral spinal fluid samples (N = 67) from 62 animals (31 horses, 24 cattle, and 7 sheep) were retrospectively evaluated. Of these 3 species, 28% (19/67) showed increased protein concentration, whereas 58% (39/67) presented mononuclear pleocytosis. In total, 37% of the samples (25/67) had protein concentration and total nucleated cell count within the reference range. Conclusions and clinical relevance: Cerebral spinal fluid from animals diagnosed with rabies was either normal or characterized by mild mononuclear pleocytosis and hyperproteinorrachia.

Analyse du liquide céphalo-rachidien chez des chevaux, bovins et moutons diagnostiqués avec la rage: une étude rétrospective de 62 cas. Objectifs: Cette étude visait à caractériser les résultats de l'analyse du liquide céphalo-rachidien (LCR) de chevaux, bovins et moutons diagnostiqués avec la rage. Animaux: L'étude a inclus 62 animaux (chevaux, bovins et moutons) diagnostiqués avec la rage dans un hôpital de référence. Méthodes: Il s'agissait d'une étude rétrospective utilisant les dossiers médicaux de grands animaux présentant des signes neurologiques et un test d'immunofluorescence directe confirmé positif pour la rage de 2003 à 2020. Les résultats de l'analyse du LCR sont présentés de manière descriptive. Résultats: Des échantillons de liquide céphalo-rachidien (N = 67) de 62 animaux (31 chevaux, 24 bovins et 7 moutons) ont été évalués rétrospectivement. Parmi ces 3 espèces, 28 % (19/67) présentaient une concentration accrue de protéines, tandis que 58 % (39/67) présentaient une pléocytose mononucléaire. Au total, 37 % des échantillons (25/67) avaient une concentration en protéines et un nombre total de cellules nucléées dans la plage de référence. Conclusions et pertinence clinique: Le liquide céphalo-rachidien des animaux diagnostiqués avec la rage était soit normal soit caractérisé par une légère pléocytose mononucléaire et une hyperprotéinorrachie.(Traduit par Dr Serge Messier).

Prevalence of the E321G MYH1 variant in Brazilian Quarter Horses.

BACKGROUND: In the Quarter Horse (QH), myosin heavy chain myopathy (MYHM), which is characterised by nonexertional rhabdomyolysis or immune-mediated myositis (IMM) with acute muscle atrophy, is strongly associated with the missense E321G MYH1 mutation. OBJECTIVES: To document the existence of MYHM in the Brazilian QH population, this study includes a case report of two related QH foals with the E321G MYH1 mutation that had clinical signs of MYHM, with histological confirmation of IMM in one of the foals. This prompted an investigation the aim of which was to determine the allele frequency of the E321G MYH1 variant across QHs using a DNA archive in Brazil. Study design Cross sectional. METHODS: To estimate the allele frequency of the E321G MYH1 variant in Brazilian QHs, 299 DNA samples from QHs used in different disciplines (reining, barrel racing, halter, cutting and racing) were analysed. DNA fragments containing the region with the mutation were amplified by PCR and used for direct genomic sequencing. RESULTS: Of the 299 genotyped QHs, 44 animals (14.7%) were heterozygous (My/N) for the E321G MYH1 variant, and 255 (85.3%) were homozygous for the wild-type allele (N/N), implying an allele frequency of 0.074. Reining horses had a significantly higher prevalence of heterozygosity than horses in other disciplines (P = .008). MAIN LIMITATIONS: The DNA samples were collected from 2010 to 2014. As only registered QHs were evaluated, the results may not reflect the actual incidence in the general population of Brazilian QHs. CONCLUSIONS: The reported cases of MYHM and the high prevalence of the MYH1 mutation found in the assessed Brazilian QH population, particularly in reining QHs, suggests that MYHM should be included in genetic screening. Reasonable control measures are important to prevent an increase in the incidence of MYHM in QHs in Brazil.

Aggrecan, IL-1ß, IL-6, and TNF-α profiles in the Articular Cartilage of Miniature Horses with Chondrodysplastic Dwarfism.

Dwarfism is a skeletal disorder that causes abnormal growth. In Miniature horses, dwarfism can occur as chondrodysplastic dwarfism, an autosomal recessive disorder associated with five mutations (D1, D2, D3*, D4 and c.6465A > T variant) in the aggrecan (ACAN) gene. The aim of this study was to evaluate the expression of aggrecan (at the gene and protein level) and specific cytokines (IL-1ß, IL-6, and TNF-α) in the articular cartilage of Miniature horses with chondrodysplastic dwarfism (D4/c.6465A > T genotype). Metatarsal bone samples from eight dwarf Miniature horses were collected for histopathological analysis, and articular cartilage was collected to detect and quantify aggrecan levels through Western blotting and determine the relative expression levels of ACAN, IL-1ß, IL-6, and TNF-α through qPCR. All affected animals presented chondrodysplasia-like lesions with disorganization of the chondrocyte layers and reduced the amount of an extracellular matrix. No significant difference in aggrecan expression levels in uncleaved samples from the dwarf and control groups (composed of phenotypically normal animals of similar age and breed (P = .7143)) was found using Western blotting. qPCR revealed that ACAN gene expression was higher in the affected animals than in normal animals (P = .0119). No significant difference in cytokine levels was detected between the groups. Mutant aggrecan may interfere with normal cellular function, leading to chondrodysplasia and the observed phenotypic findings.

Clinical findings of equine leukoencephalomalacia / Achados clínicos de leucoencefalomalácia equina

Equine leukoencephalomalacia (LEM) is a disease caused by the ingestion of food, especially corn, contaminated by fumonisin, a Fusarium verticillioides (synonymous with F. moniliforme) metabolite. The clinical signs of brain injuries have an acute onset and rapid evolution. This study aimed to describe the clinical findings in 11 animals diagnosed with LEM, including cerebrospinal fluid (CSF) analysis. Of these animals, 91% (10/11) were horses, and only 9% (1/11) were asinine. The clinical localization of the lesions was 64% (7/10) cerebral, manifested mainly by altered mental state and behavioral disturbance, and 36% (4/11) were brainstem lesions, manifested by incoordination, head tilt, nystagmus, facial hypoalgesia, difficulty in apprehension, chewing, and swallowing food. Postmortem findings revealed that 82% (9/11) of the lesions were in the cerebrum and 18% (2/11) in the brainstem. CSF findings, such as xanthochromia (43%, 3/7), hyperproteinorrachia (50%, 3/6), and pleocytosis (43%, 3/7) were observed. The affected animals showed neurological signs that were compatible with cerebral and/or brainstem injuries. The CSF from animals with LEM may present with xanthochromia, hyperproteinorrachia, and pleocytosis, reinforcing the fact that this disease should be included in the differential diagnosis of encephalomyelopathies.(AU)

A leucoencefalomalácia (LEM) é uma enfermidade que acomete equídeos causada pela ingestão de milho e seus derivados e feno contaminados pela micotoxina fumonisina, um metabólito do fungo Fusarium verticillioides (sinônimo para F. moniliforme). Os sinais clínicos apresentam início agudo e evolução rápida e são decorrentes de lesões encefálicas. O objetivo deste estudo é descrever os achados clínicos de 11 equídeos diagnosticados com LEM, incluindo a análise do líquido cefalorraquidiano (LCR). 91% dos animais afetados eram equinos e somente 9% (1/11) era asinino. A localização clínica das lesões era 64% (7/10) cerebrais, manifestadas por alterações no estado mental e comportamento e 36% (4/10) no tronco encefálico, manifestadas por incoordenação, desvio lateral de cabeça, nistagmo, hipoalgesia da face e dificuldade de apreensão, mastigação e deglutição de alimentos. Comparativamente, os achados post mortem revelaram que 82% (9/11) das lesões eram no cérebro e 18% (2/11) no tronco encefálico. Alterações no LCR, tais como xantocromia (43%, 3/7), hiperproteinorraquia (50%, 3/6) e pleocitose (43%, 3/7), foram observadas. Os animais afetados apresentaram sinais clínicos compatíveis com lesões encefálicas e/ou de tronco cerebral. O LCR de animais com LEM pode apresentar xantocromia, hiperproteinorraquia, e pleocitose, reforçando que esta doença deve ser incluída como diagnóstico diferencial de encefalomielites.(AU)

Clinical findings of equine leukoencephalomalacia

ABSTRACT: Equine leukoencephalomalacia (LEM) is a disease caused by the ingestion of food, especially corn, contaminated by fumonisin, a Fusarium verticillioides (synonymous with F. moniliforme) metabolite. The clinical signs of brain injuries have an acute onset and rapid evolution. This study aimed to describe the clinical findings in 11 animals diagnosed with LEM, including cerebrospinal fluid (CSF) analysis. Of these animals, 91% (10/11) were horses, and only 9% (1/11) were asinine. The clinical localization of the lesions was 64% (7/10) cerebral, manifested mainly by altered mental state and behavioral disturbance, and 36% (4/11) were brainstem lesions, manifested by incoordination, head tilt, nystagmus, facial hypoalgesia, difficulty in apprehension, chewing, and swallowing food. Postmortem findings revealed that 82% (9/11) of the lesions were in the cerebrum and 18% (2/11) in the brainstem. CSF findings, such as xanthochromia (43%, 3/7), hyperproteinorrachia (50%, 3/6), and pleocytosis (43%, 3/7) were observed. The affected animals showed neurological signs that were compatible with cerebral and/or brainstem injuries. The CSF from animals with LEM may present with xanthochromia, hyperproteinorrachia, and pleocytosis, reinforcing the fact that this disease should be included in the differential diagnosis of encephalomyelopathies.

RESUMO: A leucoencefalomalácia (LEM) é uma enfermidade que acomete equídeos causada pela ingestão de milho e seus derivados e feno contaminados pela micotoxina fumonisina, um metabólito do fungo Fusarium verticillioides (sinônimo para F. moniliforme). Os sinais clínicos apresentam início agudo e evolução rápida e são decorrentes de lesões encefálicas. O objetivo deste estudo é descrever os achados clínicos de 11 equídeos diagnosticados com LEM, incluindo a análise do líquido cefalorraquidiano (LCR). 91% dos animais afetados eram equinos e somente 9% (1/11) era asinino. A localização clínica das lesões era 64% (7/10) cerebrais, manifestadas por alterações no estado mental e comportamento e 36% (4/10) no tronco encefálico, manifestadas por incoordenação, desvio lateral de cabeça, nistagmo, hipoalgesia da face e dificuldade de apreensão, mastigação e deglutição de alimentos. Comparativamente, os achados post mortem revelaram que 82% (9/11) das lesões eram no cérebro e 18% (2/11) no tronco encefálico. Alterações no LCR, tais como xantocromia (43%, 3/7), hiperproteinorraquia (50%, 3/6) e pleocitose (43%, 3/7), foram observadas. Os animais afetados apresentaram sinais clínicos compatíveis com lesões encefálicas e/ou de tronco cerebral. O LCR de animais com LEM pode apresentar xantocromia, hiperproteinorraquia, e pleocitose, reforçando que esta doença deve ser incluída como diagnóstico diferencial de encefalomielites.

Serial measurements of Paraoxonase-1 (PON-1) activity in horses with experimentally induced endotoxemia.

BACKGROUND: Paraoxonase-1 (PON-1) is an antioxidant enzyme, whose activity decreases during the acute phase response in many species. Little is known about PON-1 and its role as a negative acute phase protein during septic inflammation in horses, but promising findings about its utility in diagnosing SIRS and predicting the outcome in diseased horses, were recently highlighted. The objective of the study was to investigate the behaviour of PON-1 in horses after experimentally induced endotoxemia. To this aim, PON-1 activity was measured on 66 plasma samples collected from six clinically healthy mares, previously included in another study, before and at multiple time points between 12 and 240 h after intravenous infusion of Escherichia coli O55:B5 lipopolysaccharide (LPS). RESULTS: Compared with baseline values, a progressive transient decrease of PON-1 activity was observed starting from 24 h post-infusion, with lowest values observed between 3 to 7 days post-infusion, followed by a normalisation to pre-infusion levels the tenth day. CONCLUSIONS: The results of this study suggest that measurement and monitoring of PON-1 activity might be useful to evaluate progression and recovery from endotoxemia in horses. Further studies in horses with naturally occurring sepsis are warranted.

Clinical and Therapeutic Aspects of Brazilian Native Bothrops Envenomation in Nine Horses.

In this retrospective study, clinical records of nine horses with a diagnosis of Bothrops envenomation were investigated. The accidents were classified as severe (5/9), moderate (2/9), or mild (2/9) according to the adapted bothropic snakebite severity score (BSSS). All snakebites were on the head region. The main clinical signs were local edema, blood coagulation disorders, and respiratory distress. The whole-blood clotting time (WBCT) was prolonged in all horses, and five horses presented with uncoagulable blood. All horses received specific snake antivenom according to the BSSS (six vials for severe, four vials for moderate, and two vials for mild accidents), and emergency tracheotomy was required in six horses because of respiratory distress. One horse died after eight days of hospitalization, whereas the others were discharged after nine days of hospitalization. The BSSS plus the WBCT were useful in determining the prognosis and the amount and frequency of antivenom therapy. Snakebite accidents are emergency cases; therefore, rapid and efficient therapeutic intervention will reflect positively on the prognosis.

Description of the D4/D4 genotype in Miniature horses with dwarfism.

Four causative mutations (D1, D2, D3*, and D4) of chondrodysplastic dwarfism have been described in the equine aggrecan (ACAN) gene. Homozygotes for one of these mutations and heterozygotes for any combination of these mutations exhibit the disproportionate dwarfism phenotype. However, no case description of homozygotes for D4 (D4/D4) has been reported in the literature, to our knowledge. We report 2 Miniature horses with the genotype D4/D4 in the ACAN gene. Clinically, the 2 dwarfs had a domed head that was large compared to the rest of the body, mandibular prognathism, and short and bowed limbs, mainly in the proximal region of the metatarsal bones. Radiographic examination revealed contour irregularities of the subchondral bone in the long bones and confirmed mandibular prognathism; histopathology revealed irregular chondrocyte organization. To determine the genotypes of the horses, we performed DNA extraction from white blood cells, PCR, and Sanger sequencing. Genotyping demonstrated that these 2 animals had the D4/D4 genotype in the ACAN gene. The D4/D4 dwarfs were clinically similar to animals with the other ACAN genotypes reported for this disease. Identification of heterozygous animals makes mating selection possible and is the most important control measure to minimize economic losses and casualties.

Prevalence of the Mutations Responsible for Glanzmann Thrombasthenia in Horses in Brazil.

Glanzmann's thrombasthenia (GT) is an autosomal recessive inherited disorder characterized by changes in platelet aggregation, leading to hemorrhage and epistaxis. To date, two independent mutations have been described in horses and associated with this disorder, a point mutation (c.122G > C) and a 10-base-pair deletion (g.1456_1466del) in the Integrin subunit alpha2ß gene (ITGA2B) of horses of different breeds (Quarter Horse, Thoroughbred, Oldenburg, and Peruvian Paso). ITGA2B codifies the αIIb subunit of the αIIbß3 integrin, also termed platelet fibrinogen receptor. Horses with GT have been diagnosed in the USA, Canada, Japan, and Australia. However, there are no studies on the prevalence of GT in horses. The aim of this study is to evaluate the prevalence of the mutations responsible for GT in horses in Brazil. A total of 1053 DNA samples of clinically healthy Quarter Horse (n = 679) and Warmblood horses (n = 374) were used. DNA fragments were amplified by PCR and sequenced. The genotype of each animal was analyzed and compared to the nucleotide sequence of the ITGA2B gene found on GenBankTM. There were no carriers in the analyzed samples, that is, all animals tested were wild type. Therefore, under the conditions in which this study was carried out, it can be inferred that GT seems to be extremely rare in the population of Quarter Horses and Warmbloods in Brazil, although it is not possible to affirm that there are no horses carrying mutated alleles in Brazil.

Canine POMC deletion (P187fs) allele frequency in Labrador Retrievers in Brazil / Frequência de alelos mutados (P187fs) no POMC de cães Labrador Retriever no Brasil

The Labrador Retriever is among the main breeds with the greatest predisposition to obesity. Several factors, especially the interrelationships between food management, exercise and social factors; influence the likelihood of a dog becoming obese. Furthermore, genetic factors are also responsible for obesity in dogs, and in Labrador Retriever, a frameshift mutation (P187fs) in pro-opiomelanocortin (POMC) gene is strongly associated with obesity. There is no knowledge of studies that have previously evaluated the prevalence of the canine POMC deletion (P187fs) in Brazilian Labrador Retriever. Therefore, the objective of this study was to investigate this mutation in Labrador Retriever dogs in Brazil. Of the 108 Labrador Retrievers that were assessed in this study, 59 were from a previous study, composed by animals assisted in a veterinary hospital with unknown lineage, and 49 were from a prospective study, composed of 19 pet and 30 assistance/rescue Labrador Retriever dogs. The obesity risk and appetite questionnaire were applied, with some modifications, to tutors of the animals used in the prospective study. Fragments of the DNA, containing the mutation, were amplified by PCR and submitted to direct gene sequencing. The allele frequency of the mutation was 21.3% and was out of Hardy-Weinberg equilibrium (P<0.05). Using only the data of animals with known lineage, the presence of the mutated allele was higher in the Assistance/rescue Group than Pet Group (P<0.01), furthermore, the allele frequencies observed in Assistance Group (31.7%) was out of Hardy-Weinberg equilibrium (P<0.05), while that in the Pet Group (18.4%) was in equilibrium (P>0.05). Although the mutation has increased the food-motivation in the assistance/rescue dogs, other variables, especially frequent exercising, favored that these animals maintained the ideal body weight (body condition score = 5). In summary, the Hardy-Weinberg disequilibrium observed in the allele distribution of the deletion POMC_P187fs in this study, independently of the Labrador Retriever group assessed, suggesting the possibility of positive selection of the mutated allele, which may lead to the maintenance of this deleterious allele in the studied population.(AU)

O Labrador Retriever é uma das principais raças caninas com maior predisposição à obesidade. Vários fatores, especialmente as interrelações entre a alimentação, exercício e fatores sociais, influenciam a probabilidade de um cão se tornar obeso. Além disso, fatores genéticos são também responsáveis pela obesidade em cães, e no Labrador Retriever a mutação "frameshift" P187fs no gene pró-opiomelanocortina (POMC) está fortemente associada à obesidade. Não existem estudos prévios de prevalência da deleção P187fs no gene POMC em cães Labrador Retriever no Brasil. Portanto, o objetivo deste estudo foi investigar esta mutação em cães da raça Labrador Retriever no Brasil. Dos 108 Labradores Retrievers avaliados neste estudo, 59 eram de um estudo retrospectivo (composto por animais atendido no hospital veterinário e sem linhagem conhecida) e 49 eram de um estudo prospectivo (composto por 19 cães pet e 30 cães de assistência/resgate). Um questionário de risco de obesidade modificado foi aplicado nos tutores dos animais usados no estudo prospectivo. Fragmentos de DNA, contendo a mutação, foram amplificados por PCR e submetidos ao sequenciamento gênico direto. A frequência alélica da mutação foi de 21,3% e estava fora do equilíbrio de Hardy-Weinberg (P<0,05). Usando somente os dados dos animais de linhagem conhecida, a presença do alelo mutado foi maior no Grupo de cães de Assistência/resgate que no Grupo de Pets (P<0,01), além disso, as frequências alélicas nos Grupos de Assistência/resgate (31,7%) e no de pets (18,4%) estavam fora e em equilíbrio de Hardy-Weinberg (P<0,05), respectivamente. Embora a mutação tenha aumentado a motivação pelo alimento em cães Labrador Retriever do Grupo de Assistência/resgate, outras variáveis, especialmente o frequente exercício, favoreceu a manutenção o peso corporal ideal (peso corporal = 5). Em resumo, o desequilíbrio de Hardy-Weinberg observado na distribuição do alelo POMC_P187fs observado neste estudo, independentemente do grupo de Labrador Retriever avaliado, sugere a possibilidade de uma seleção positiva para o alelo mutado, o qual poderá levar a manutenção desse alelo deletério nesta população.(AU)

Allele Frequency of the C.5G>A Mutation in the PRCD Gene Responsible for Progressive Retinal Atrophy in English Cocker Spaniel Dogs.

Progressive retinal atrophy (PRA) due to the c.5G>A mutation in the progressive rod-cone degeneration (PRCD) gene is an important genetic disease in English cocker spaniel (ECS) dogs. Because the prevalence of this disease has not been verified in Brazil, this study aimed to evaluate the allele frequency of the c.5G>A mutation in the PRCD gene. Purified DNA from 220 ECS dogs was used for genotyping, of which 131 were registered from 18 different kennels and 89 were unregistered. A clinical eye examination was performed in 28 of the genotyped animals; 10 were homozygous mutants. DNA fragments containing the mutation region were amplified by PCR and subjected to direct genomic sequencing. The prcd-PRA allele frequency was 25.5%. Among the registered dogs, the allele frequency was 14.9%; among the dogs with no history of registration, the allele frequency was 41%. Visual impairment was observed in 80% (8/10) of the homozygous mutant animals that underwent clinical eye examination. The high mutation frequency found in this study emphasizes the importance of genotyping ECSs as an early diagnostic test, especially as part of an informed breeding program, to avoid clinical cases of PRA.

Spontaneous poisoning by Palicourea marcgravii (Rubiaceae) in a sheep herd in southeastern Brazil.

Palicourea marcgravii (Rubiaceae) is considered the most important toxic plant affecting livestock farming in Brazil. This study describes an outbreak of spontaneous poisoning by P. marcgravii in sheep. Forty-nine sheep died while showing clinical signs of sudden death after having access to the plant. During the necropsy, P. marcgravii leaves were observed in the rumens of the animals. Histopathological analysis demonstrated hydropic degeneration of the kidneys. Monofluoracetate concentration obtained in Palicourea samples was 0.53% (5.3 µg/mg). These findings collectively indicate that the affected animals died from poisoning due to P. marcgravii.

Molecular detection of albinism gene in Brazilian buffalo herds (Bubalus bubalis) / Detecção molecular do gene do albinismo em rebanhos de búfalos (Bubalus bubalis) do Brasil

Albinism is a genetic disease characterized by deficient melanin production making affected animals more susceptible to skin problems, negatively influencing production systems of the same. In buffalo, a nonsense mutation (c.1431G>A) in the tyrosinase gene was already described, which is responsible for the oculocutaneous albinism buffalo phenotype. However, prevalence studies have never been performed for this anomaly in Brazil. Therefore, the objective of this study was to investigate this mutation in buffalo herd in Brazil. Of the 315 buffalo tested with no albinism phenotype evident, 11 (3.5%) were heterozygous for the mutation and none were mutated homozygous, showing the existence of the albinism gene in buffalo production herds and proving the importance of prevalence studies for hereditary diseases in order to prevent the dissemination of these same genes and their negative productivity consequences.(AU)

O Albinismo é uma doença genética caracterizada pela deficiência na produção de melanina, o que torna os animais afetados mais susceptíveis a problemas cutâneos e influencia negativamente a criação destes animais. A mutação nonsense (c.1431G>A) no gene da tyrosinase já foi descrita como responsável pelo albinismo oculocutâneo em búfalos, entretanto estudos prévios sobre a prevalência dessa mutação ainda não foram realizados no Brasil. Portanto, o objetivo deste estudo foi avaliar a presença desta mutação em uma população de búfalos brasileiros. Foram genotipados 315 búfalos clinicamente normais, ou seja, sem o fenótipo albino evidente. Desses, 11 (3,5%) eram heterozigotos para a mutação (N/TYR) e os demais eram homozigotos selvagens (N/N). Este resultado demonstra que o alelo mutado para o albinismo em búfalo está presente no rebanho brasileiro e aponta a importância de estudos de prevalência de enfermidades hereditárias com o objetivo de prevenir a disseminação desses alelos mutados, minimizando os prejuízos.(AU)

Prevalence of mutations responsible for glycogen storage disease type-II and congenital myasthenic syndrome in Brazilian Brahman cattle / Prevalência de mutações responsáveis pela estocagem de glicogênio tipo II e síndrome miastênica congênita em bovinos brasileiros da raça Brahman

Glycogen storage disease type II (GSD-II) and congenital myasthenic syndrome (CMS) are important autosomal recessive disorders in Brahman cattle. The objective of this study was to investigate the presence of mutations responsible for GSD II (E7, c.1057_1058delTA; and E13, c.1783C>T) and CMS (c.470del20) in purebred Brazilian Brahman cattle and in purebred Brahman bulls that were routinely used in breeding programs in Brazil. A total of 276 purebred Brahman cattle (167 females and 109 males, with ages ranging from 12-24 months) and 35 frozen semen samples taken from purebred Brahman bulls (22 bulls from the USA, 11 Brazilian bulls, one Argentine bull and one Australian bull) were used in this study. Genomic DNA was purified from hair root samples and from semen samples. Purified DNA was used in PCR genotyping to mutations c.1057_1058delTA (E7) and c.1783C>T (E13) in the GAA gene and c.470del20 in the CHRNE gene. The PCR products were purified and sequenced. The genotypic frequencies per polymorphism were estimated separately. Of the 276 Brahman cattle tested, 7.3% were identified as heterozygous for E7. All Brahman cattle studied were homozygous for the wild-type E13 allele. The E7 mutations was identified as heterozygous in 8.6% (3/35) of the commercial semen samples, whereas the E13 mutations was not identified. The c.470del20 mutation was identified as heterozygous in 0.73% of the hair root samples, but this mutation was not present in any semen sample assessed. No study had previously evaluated the prevalence of mutations responsible for GSD II or CMS in Brazilian Brahman cattle. In summary, the E7 and c.470del20 mutations are present in the Brazilian Brahman herd, and control measures should be adopted to prevent an increase in the incidence of GSD-II and CMS in Brahman cattle in Brazil.(AU)

A doença de armazenamento de glicogênio tipo II (DAG-II) e a síndrome miastênica congênita (SMC) são importantes doenças autossômicas recessivas no gado Brahman. O objetivo deste estudo foi investigar a presença das mutações responsáveis pela DAG-II (E7, c.1057_1058delTA; e E13, c.1783C>T) e pela SMC (c.470del20) em bovinos da raça Brahman e em touros Brahman que são rotineiramente utilizados em programas de reprodução no Brasil. Um total de 276 amostras de bulbo piloso de bovinos Brahman (167 fêmeas e 109 machos, com idade variando de 12 a 24 meses) e 35 amostras de sêmen congeladas de touros Brahman (22 touros americanos, 11 touros brasileiros, um touro argentino e um touro australiano) foram usados neste estudo. O DNA genômico foi purificado, das amostras de bulbo piloso e de sêmen, e utilizado na genotipagem por PCR das mutações c.1057_1058delTA (E7) e c.1783C>T (E13) no gene GAA e c.470del20 no gene CHRNE. Os produtos de PCR foram purificados e sequenciados. A frequência genotípica para cada polimorfismo foi estimada separadamente. Dos 276 Brahman testados, 7,3% foram identificados como heterozigotos para E7. Todos os Brahman foram homozigotos wild-type para o alelo E13. A mutação E7 foi identificada em homozigose em 8,6% (3/35) das amostras de sêmen comerciais, enquanto que a mutação E13 não foi identificada. A mutação c.470del20 foi identificada em heterozigose em 0,73% das amostras de bulbo piloso, mas esta mutação não estava presente nas amostras de sêmen avaliadas. Nenhum estudo prévio avaliou a prevalência das mutações responsáveis pela DAG-II ou SMC em bovinos Brahman brasileiro. Em suma, as mutações E7 e c.470del20 estão presentes no rebanho Brahman brasileiro, e medidas de controle devem ser adotadas para prevenir o aumento da incidência da DAG-II e SMC em bovinos da raça Brahman no Brasil.(AU)

Proteinograma e concentração sérica de IgG em potros, do nascimento aos trinta dias de vida, tratados com plasma / Proteinogram and serum IgG concentration in newborn foals up to thirty days of life treated with plasma

Este trabalho teve por objetivo avaliar o proteinograma e concentrações séricas de IgG (após a padronização de teste ELISA) em potros do nascimento aos trinta dias de idade, antes e depois de mamarem colostro e serem tratados com plasma por via intravenosa. Foram utilizados 20 potros e suas respectivas mães, além de quatro animais doadores de plasma. Foram colhidas amostras de sangue dos potros em cinco momentos, logo após o nascimento e antes de mamar colostro (M1), dez horas após nascimento (M2), 24 horas após nascimento e previamente administração do plasma sanguíneo (M3), 48 horas de vida e 24 horas após administração do plasma sanguíneo (M4), e 30 dias após nascimento (M5). Foram colhidos sangue e colostro das éguas progenitoras no momento do parto. A concentração de proteína total (PT) e albumina foram determinadas em analisador bioquímico, a concentração de PT também foi avaliada em refratômetro manual. O fracionamento proteico foi realizado utilizando eletroforese em gel de agarose. A densidade do colostro foi avaliada com colostrômetros de refração BRIX e de densidade específica. A concentração de IgG total de todas as amostras foi determinada por teste ELISA. Com o sistema de ELISA aqui proposto foi possível determinar concentrações de IgG em amostras de soro, plasma e colostro equino com adequada repetibilidade. A média ± desvio padrão da concentração sérica de IgG dos potros ao nascer, foi de 15±8mg/dL, com dez horas de vida foi de 2.408±608mg/dL, se manteve em níveis semelhantes até 48 horas (2.364±784mg/dL) e diminuíram significativamente aos 30 dias de vida (1.414±586mg/dL). A concentração sérica e colostral de IgG nas éguas foi de 1.746±505mg/dL e 7.714±2.619mg/dL, respectivamente. A concentração plasmática de IgG dos doadores de plasma foi de 2.026±148mg/dL. Houve correlação positiva entre as concentrações séricas de IgG e PT (r=0,69 para refratômetro e r=0,76 para bioquímico), GT (r=0,81) e gamaglobulina (r=0,85). Dez horas após o nascimento foi possível verificar a transferência de imunidade passiva, possibilitando adotar medidas profiláticas e/ou terapêuticas em haras de criação de cavalos. Considerando que a proteína total, globulinas totais e fração γ-globulina apresentam correlação com IgG, estas determinações são úteis para monitorar os potros após mamarem o colostro. Um litro de plasma administrado às 24 horas de vida não foi suficiente para aumentar as concentrações séricas de IgG, 24 horas após transfusão, em potros com adequada transferência de imunidade passiva.(AU)

The aim of this study was to evaluate serum protein and serum IgG concentrations (after a direct enzyme immunoassay test ELISA optimization) in newborns foals from birth to thirty days of life before and after colostrum consumption and intravenous treatment with plasma. Twenty foals and their respective progenitors as well as four plasma donor's horses were used. Blood samples were obtained from newborn foals at five time points, immediately after birth and before colostrum intake (M1), ten hours after birth (M2), 24 hours after birth and prior administration of blood plasma (M3), 48 hours after birth and 24 hours after plasma administration (M4), and 30 days after birth (M5). Blood and colostrum samples were collected from the progenitor mares immediately postpartum. Concentration of total protein (TP) and albumin were determined using a biochemical analyzer. The TP concentration was also measured by refractometer. Fractions of total serum protein were separated using agarose gel electrophoresis. Colostrum density was evaluated using BRIX refractometer and specific density colostrometer. Total IgG concentration was determined by an enzyme-linked immunosorbent assay. With the ELISA system proposed here it was possible to determine IgG concentrations in serum, plasma, and equine colostrum samples with adequate repeatability. Serum IgG concentration in foals at birth was 15±8mg/dL (mean ± standard deviation) raising at ten hours (2,408±608mg/dL) and remaining at similar levels up to 48 hours of life (2,364±784mg/dL), and decreasing significantly at 30 days of age (1,414±586mg/dL). Serum and colostrum IgG concentrations of mares were 1,746±505mg/dL and 7,714±2,619mg/dL, respectively. The plasma IgG concentrations from donor mares were 2,026±148mg/dL. Total protein, total globulins, and γ-globulin fraction showed correlation with IgG. Ten hours post birth was an adequate time to verify the transfer of passive immunity, allowing to adoption prophylactic and/or therapeutic measures in a horse farms. One liter of plasma administered at 24 hours of life was not sufficient to raise serum IgG concentrations in foals without passive immunity transfer failure.(AU)

Frequency of Equus caballus papillomavirus in equine aural plaques.

Despite the reported association between aural plaques and the presence of Equus caballus papillomavirus (EcPV), there are few data regarding the distribution of viral types in different geographic regions or possible correlations for different papillomaviruses and lesion characteristics. We detected the presence and frequency of EcPV (1-7) DNA in aural plaque biopsies of horses from different regions of Brazil and identified the patterns of these infections or coinfections and their possible association with lesion severity. A total of 108 aural plaque biopsies from horses in the 5 geopolitical regions of Brazil were examined. We performed PCR to detect EcPV DNA in the biopsies. At least 1 type of EcPV was detected in 97% of the samples. EcPV coinfection was observed in 59% of the samples. Compared to the other viruses, EcPV-4 was found at the highest frequency in coinfection (84%) or individually identified (32%). EcPV-2 and -7 were not detected. No significant association was found between lesion characteristics (type and distribution) and either the viral type detected or the presence of coinfection. EcPV is widely distributed in Brazil, both isolated and in coinfection; the viral type does not appear to influence the clinical characteristics of equine aural plaques.